1. Field of Invention
This invention relates generally to connecting a drive wheel axle and a track roller frame on a vehicle, and more particularly to accommodating forces in a drive wheel axle transmitted through a track roller frame.
2. Description of Related Art
A tractor for agricultural use can have wheels or tracks in contact with the ground surface. A cultivator is one agricultural implement that is often pulled by a tracked tractor, which has an advantage in a planted field over a wheeled tractor of having its weight more evenly distributed on the ground surface. A tracked tractor generally has two track assemblies, one on each of the left and right sides of the tractor. A track assembly typically includes a rubber track that forms a loop around a drive wheel, a number of mid-rollers, and an idler wheel. During use of the tractor, the drive wheel rotates and engages the rubber track, thereby causing the rubber track to rotate around a path defined by the drive wheel and the idler wheel. The rotation of the rubber track causes it to engage the ground, thereby propelling the tractor on the ground surface of the crop field.
A drive wheel of the tractor is rotatably attached to the drive wheel axle. Typically, the drive wheel axle has no freedom of movement other than the rotational motion provided by gears of a power train. However, in some tractor models, the track roller frame between a drive wheel and a corresponding idler wheel slightly twists and shifts from side to side in use as the tractor travels, especially over uneven terrain. Accordingly, there is a need for a structure for connecting the drive wheel axle and the track roller frame that has an ability to absorb or oppose the load caused by the positional misalignments between the drive wheel axle and the track roller frame.